kbuild: refactor quiet_modtag

Backport from kernel
commit 45c4372d00 ("kbuild: refactor quiet_modtag")

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/scripts/Makefile.build b/scripts/Makefile.build
index 2944629..ed58bca 100644
--- a/scripts/Makefile.build
+++ b/scripts/Makefile.build
@@ -113,18 +113,13 @@
 	$(if $(part-of-module),                           \
 		$(KBUILD_CFLAGS_MODULE) $(CFLAGS_MODULE), \
 		$(KBUILD_CFLAGS_KERNEL) $(CFLAGS_KERNEL))
-quiet_modtag := $(empty)   $(empty)
+quiet_modtag = $(if $(part-of-module),[M],   )
 
 $(real-objs-m)        : part-of-module := y
 $(real-objs-m:.o=.i)  : part-of-module := y
 $(real-objs-m:.o=.s)  : part-of-module := y
 $(real-objs-m:.o=.lst): part-of-module := y
 
-$(real-objs-m)        : quiet_modtag := [M]
-$(real-objs-m:.o=.i)  : quiet_modtag := [M]
-$(real-objs-m:.o=.s)  : quiet_modtag := [M]
-$(real-objs-m:.o=.lst): quiet_modtag := [M]
-
 # Default for not multi-part modules
 modname = $(basetarget)